Theodosius I

Theodosius Flavius (347-395 CE) was an emperor of the Roman Empire, the last emperor to rule over the east and west united. He succeeded Flavius Valens as emperor in 379 AD following the Battle of Adrianople and the emperor's death, and became one of Rome's greatest leaders.

Biography
Flavius was born in Cauca in Roman Hispania (now Coca, Spain) to an Italian aristocratic family, son of Theodosius Flavius the Elder. He accompanied his father to Britannia in 368 to quell the Great Conspiracy uprising by the Romano-British and Celts, but when his father was executed, he retired to Hispania.

In 375, with the death of Valentinian I, Rome fell into chaos. Valentinian II and Gratian governed the Western Roman Empire as Flavius Valens ruled the Eastern Roman Empire. Theodosius became Augustus when Valens was killed in 379 AD, invited to rule by Gratian. When Valentinian II died by suicide in 392, Theodosius made his son Arcadius Eastern Roman emperor. With Valentinian's death, Theodosius defeated Arbogast's rebels at the Battle of Frigidus and restored peace. He died in 395, a year later.